GLOBAL KEEP ORIGINAL FORMAT/THEME OPTION
I move many slides from one presentation to the next, and sometimes the themes are different and I am forever having to tell PPT to use the source formatting parameters. it's just plain annoying.
On the Mac there should be a way of setting the default so that the slide looks exactly like the original wherever it is transferred to.
I don't use styles and themes -- I imagine there are many PPT users like me.